Process of producing antimony oxides



Aug. 23, 1932. J. J. LISTRAT 1,873,774

PROCESS OF PRODUCING ANTIMONY OXIDES Filed Dec. 9. 1927 INVENTOR WITNESSES 7azz all???" w. BY

ATTO R N EY Patented Aug. 23, 1932 PATENT QFFEQE Jenn aosm'n LISTRAT, OFCLAMART, SEINE, raanon PROCESS OF PRODUCING ANTIMONY OXIDES Application filed December 9, Serial No. 238,909.

The present invention is concerned with-the process for simultaneously and continuously producing antimony oxide at approximately 99% and antimony oxide at approximately 96-98%; the former being very white and having peculiar physical qualities and a constant well determined chemical composition, while the latter is of a lesser although marketable value.

An object of the invention is to produce these oxides in one operation from ordinary gray antimony ore (antimony trisulphide) in a special type of melting, disassociating and oxidizing furnace, by a process which requires the application of no external heat when once under way.

More specifically, the process includes the use of two exothermic reactions Which supply sufficient heat for carrying out the entire process from the melting of the ore to the production of the final 99% oxide.

Other objects of the invention are to provide a process of this character which may be carried out with expedition, economy and facility.

With the above noted and other objects in view, the invention consists in certain novel features of construction and combinations and arrangements of parts, as will be more fully icreinafter set forth and pointed out in the claims. The invention may be more fully understood from the following description in connection with the accompanying drawing, wherein- Fig. 1 is a longitudinal sectional view through a triple cupola furnace in which the process is carried out.

Fig. 2 is a transverse sectional. view on the line 2-2 of Fig. 1.

The drawing described above is diagrammatic, and for purposes of simplification, omit any showing of vapor conductors, oxide recovery apparatus and the like.

The process may be more readily understood by lirst describing the apparatus which consists of a furnace 1O havin three cupola chambers 11, 12 and 13 therein. The central chamber 12 communicates with the air, and m the end chambers 11 and 13 are adapted to communicate directly with recovery apparatus (not shown), these chambers receiving air through inclined pipes 14 extending downwardly through the end walls of the furnace and entering the lower ends of the chambers.

The bottom of the chamber 12 communicates with the bottoms of the chambers 11 and 13 through relatively low passageways 15. Chamber 12 is also provided with a suitable tap 16 at the proper level for a purpose'which will be later described.

In carrying out the process, the ordinary gray antimony ore or antimony trisulphide sb ss is introduced into the central cupola chamber 12. Any suitable source of external heat is used for originally heating the central chamber, after which, when the process gets under way, the exothermic reactions of the process provide all of the necessary heat. The antimony ore in its usual condition contains a certain amount of galena, iron pyrites, quartz, spar and similar materials. In this chamber the ore is subjected to the proper degree of heat for melting and disassociating it. The molten antimony Sb sinks to the bottom under the molten ore upon which floats" the gangue indicated at 17. This gangue may be drained off at proper intervals through the tap 16.

The molten antimony flows through the passageway into the chambers 11 and 13, sealing the passageways 15 and covering the lower ends of air inlet pipes 1 1. The cross sectional areas of the three cupola chambers are so proportioned that the molten antimony in chambers 11 and 13 maintains thegangue in chamber 12 at a higher level than the level of antimony in the chambers 11 and 13.

The first exothermic reaction is produced directly in the chamber'12 due to the oxidation of the vapors of the antimony trisulphide and also of the oxidation of the vapors of free sulphur which are released. These vapors may be separated and the antimony oxide (96 to 98%) recovered in any suitable manner (not shown).

The second exothermic reaction is produced by forcing a suitable quantity of air through the molten antimony in the chambers 11 and 13. i

:The antimony oxide, which in a volatile form is drawn 0]? from the chambers 11 and 13 and recovered, is approximately 99% pure. It is very white and has a chemical composition which is well determined and constant. The exothermic reaction incidental to the production of this antimony oxide in the chambers 11 and 13, is very violent, and sufficient heat is produced and conducted through the molten antimony into the chamber 12 to render the use of any external heating means unnecessary. The violence of the reaction may of course be determined by the rate of introduction of air into the chambers 11 and 13, and a temperature maintained which is sufficient to melt and disassociate the ore in the chamber 12.

The antimony oxide recovered from the vapors escaping from the chamber 12 is approximately 96 to 98% pure, and while inferior to that produced in the other chambers, is of a marketable quality.

From the foregoing it will be apparent that I have used the released heat caused by the combining reaction of antimony and oxygen to maintain the necessary temperatures throughout the entire process from the original melting of the ore to the final production of the very white 99% antimony oxide. It will also be noted that both antimony oxides are produced in one operation and simultaneously by a substantially continuous process.

The 99% antimony oxide recovered from y the chambers 11 and 13 is for the most part high and uniform quality.

So far as the apparatus is concerned, it will Sb O containing a very small quantity of Sb' O The oxide recovered from the central chamber 12 contains a somewhat larger and varying quantity of Sb O The reason for this slight inferiority of quality in the oxide recovered from the central chamber is due to the fact that oxidizing conditions are diflicult to control in the central chamber where vapors rather than molten metal are oxidized, and where the percentages of vapors and oxidizing air are continually varying. In the end chambers, measured quantities of air may be blown through the molten metal, and the oxidization accurately controlled to produce a product of be apparent that numerous slight changes and alterations might be made without departing from the spirit and scope of the appended claims.

I claim:

1. A process for producing antimony oxide from antimony sulphide ore, which comprises heating the sulphide ore to the proper degree of heat for dissociating the ore into molten antimony, sulphur vapors and antimony tri-sulphide vapors in a space while oxidizing the sulphur vapors and the antimony tri-sulphide vapors in said space, confining the molten antimony in a second space and passing a stream of air through the molten antimony for oxidizing the antimony, the exothermic reaction caused by the oxida tion being adapted to maintain the proper temperature for the dissociation of the ore without external heat.

2. The process of producing antimony oxide from antimony sulphide which comprises melting the ore in a space which is open to the atmosphere to cause dissociation of the ore into molten antimony, vapors of sulphur and antimony tri-sulphide while collecting the molten antimony in the first mentioned space and in a closed space in open communication with the first mentioned space, passing air through the molten antimony in the closed and open space for causing oxidation of the sulphur and antimony trisulphide vapors and also oxidation of the molten antimony in the closed space, the exothermic reaction caused by such oxidation being adapted to maintain the proper temperature for the dissociation of the ore without external heat.

Signed a New York in the county of New York and State of New York this 7th day of December A. D. 1927.

JEAN JOSEPH LISTRAT. 

